58 



HOTBED AND COLD FRAME 



directly in the beds from 4 to 6 inches of good garden loam 



is necessary. 



After the manure has been placed in the pit, a secondary 



fermentation will take place, and the heat will often rise 

 as high as 100° to 110° F. At this time 



psPT^^^^sr,,-^—^-— — : it would be very detrimental to plant 

 either seeds or plants in the soil, and a 

 week or ten days should lapse after the 

 hotbed is made before any planting is 

 done. This secondary heating continues 

 for a longer or a shorter period, and 

 gradually falls until it reaches 6.5° to 75° 

 F., where it remains more or less con- 

 stant throughout the life of the hotbed. 

 By placing a soil thermometer in the bed 

 it is easy to determine the proper time to 

 plant, which will vary from a few days 

 to a couple of weeks, depending upon 

 the depth of the pit, the freshness of the 

 manure, and several other factors. 



COLD FRAME. 



A cold frame is a bed covered with glass 

 where no heat is provided except the 

 sun's rays. All the conditions such as 

 the location, the arrangement, the man- 

 agement, etc., that are recommended for 

 hotbeds apply with equal force to cold 

 frames. The cold frame, as a rule, is used 

 later in the season than the hotbed. No 

 pit is required for the cold frame. It 

 simply consists of a wooden frame placed 

 on top of the soil. Occasionally manure 

 is piled around the sides of the frame to 

 offer a little protection. The cold frame 

 is usually employed for the "hardening off" of plants later 

 in the season, but on a small scale the hotbed will serve 

 this purpose. As a rule, the cold frame requires more 



Fig. 16. — A soil ther- 

 mometer. 



